A mixture of antibody molecules (that are specific for a given antigen) that has been purified from an immunized (to that given antigen) animal’s blood. Such antibodies are polyclonal in that they are the products of many different populations of antibody-producing cells (within the animal’s body). Hence they differ somewhat in their precise specificity and affinity for the antigen. Years ago, antibodies (then called antitoxin) that were purified from an immunized animal’s blood (e.g., a horse) were injected into humans suffering from certain diseases (e.g., diphtheria). In these cases the pathogen had caused disease by secreting large amounts of toxin into the victim’s bloodstream. The antitoxin combined quantitatively (e.g., 1:1, 2:1, 1:2, 1:3, 3:1, etc.) with, and neutralized the toxin (for those few diseases for which it was applicable). Vaccines are now used instead, because of the adverse immune response caused by the horse’s blood (antigens).<\/p>\n
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A mixture of antibody molecules (that are specific for a given antigen) that has been purified from an immunized (to that given antigen) animal’s blood. Such antibodies are polyclonal in that they are the products of many different populations of antibody-producing cells (within the animal’s body). Hence they differ somewhat in their precise specificity and […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-38913","post","type-post","status-publish","format-standard","hentry","category-p"],"yoast_head":"\n